How do you solve the equation by factoring and the zero-product rule: $4x^2-25$ ?

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Answer 1 · 2016-12-06T18:26:51

$+-5/2$

Method 1

$4x^2-25=0$

factorise by difference of squares

$(2x+5)(2x-5)=0$

solving for each bracket

$2x+5=0=>2x=-5=>x=-5/2$

$2x5=0=>2x=5=>x=5/2$

Method 2

rearrange the eqn for $""x$

$4x^2-25=0=>4x^2=25$

$x^2=25/4$

$x=+-sqrt(25/4)=+-5/2$

How do you solve the equation by factoring and the zero-product rule: 4x^2-254x^2-25?